(1) Field of the Invention
The present invention generally relates to a tray guide mechanism of a disk drive, and more particularly to an improvement of a tray guide mechanism which guides a movement of a tray in one of an inserting direction to insert the tray into a chassis of a disk drive and an ejecting direction to eject the tray from the chassis, a disk placed on the tray being accessed by the disk drive.
(2) Description of the Related Art
A CD-ROM (Compact Disk-Read Only Memory) disk drive for use within a notebook-size personal computer is known. A CD-ROM is a type of an optical disk which is capable of storing a large amount of data including programs or database data. The CD-ROM, which is placed in the CD-ROM disk drive, is accessed by a laser pickup of the CD-ROM disk drive so that data is reproduced from the CD-ROM.
A CD-ROM disk apparatus having a tray guide mechanism for guiding a movement of the tray in an inserting direction of the disk apparatus or an ejecting direction of the disk apparatus is known. The tray is provided for placing a disk thereon, and the disk being placed on the tray is the CD-ROM which is accessed by the CD-ROM disk apparatus. The tray with the disk being placed thereon is inserted into the disk apparatus in the inserting direction or ejected from the disk apparatus in the ejecting direction with the aid of the tray guide mechanism.
FIG. 16 shows a conventional CD-ROM disk apparatus of the above type. FIG. 17 shows a tray guide mechanism of the CD-ROM disk apparatus in FIG. 16. For example, Japanese Laid-Open Patent Application No.7-254199 discloses a CD-ROM disk apparatus of the above type.
As shown in FIG. 16, the CD-ROM disk apparatus includes a tray 1 which is slidably arranged therein and movable in both an ejecting direction "A" and an inserting direction "B". When a disk (not shown) is loaded into the disk apparatus, the tray 1 with the disk being placed thereon is manually inserted into the disk apparatus in the inserting direction B and set at a loaded position in the disk apparatus.
In the disk apparatus in FIG. 16, a drive unit is provided below the tray 1. A turntable 2 which is rotated by a spindle motor (not shown) is attached to the drive unit, and the disk being placed on the tray 1 is held on the turntable 2. An optical pickup 3 for accessing the disk to read out data from the disk is attached to the drive unit. Further, a pickup moving unit (not shown) for moving the pickup 3 in a radial direction of the disk is attached to the drive unit.
In the above disk apparatus, an ejection unit for ejecting the tray 1 from a chassis 9 is provided. A front bezel 1b is attached to a front end surface of the tray 1. The front bezel 1b includes a rectangular opening which extends laterally in the front bezel 1b. An ejection switch part 4 is attached to the tray 1 and provided in the opening of the front bezel 1b.
When the ejection switch part 4 is manually pressed, the tray 1 is ejected from the chassis 9 by the ejection unit. When the ejecting operation is performed, the tray 1 is set at an ejected position by the ejection unit, and the tray 1 at the ejected position is further pulled out from the chassis 9 to a disk-change position by the operator. When the tray 1 is set at the disk-change position, the tray 1 is fully exposed and the disk on the tray 1 can be changed with a new one.
In the disk apparatus in FIG. 16, a tray guide mechanism 5 is provided to guide the movement of the tray 1 in either the inserting direction or the ejecting direction. FIG. 17 shows the tray guide mechanism 5 of the conventional disk apparatus in FIG. 16. The tray guide mechanism 5 includes a pair of movable rails 6, a pair of fixed rails 7, and a pair of slide rails 8.
The movable rails 6 are secured to the sides of the tray 1 by screws and arranged such that the movable rails 6 are movable to the chassis 9. The fixed rails 7 are secured to the chassis 9 by screws, and the fixed rails 7 are arranged on the chassis 9 so that the fixed rails 7 extend in directions parallel to the movable rails 6. The slide rails 8 are movably arranged between the movable rails 6 and the fixed rails 7 so that the slide rails 8 are movable to both the movable rails 6 of the tray 1 and the fixed rails 7 of the chassis 9.
As shown in FIG. 17, a pinion 8a is rotatably supported in the middle of each of the slide rails 8. Each of the movable rails 6 includes a rack 6a, and the pinion 8a of each slide rail 8 is engageable with the rack 6a of the movable rail 6. Each of the fixed rails 7 includes a rack 7a, and the pinion 8a of each slide rail 8 is engageable with the rack 7a of the fixed rail 7.
In the above tray guide mechanism 5, when the tray 1 is pulled out from the chassis 9, the movable rails 6 are moved relative to the slide rails 8 in the ejecting direction A by a distance "La", and the slide rails 8 are also moved relative to the fixed rails 7 in the ejecting direction A by a distance "Lb". When the slide rails 8 are moved relative to the fixed rails 7, the pinions 8a are rotated on the racks 7a of the fixed rails 7. As the pinions 8a are rotated and the tray 1 is supported on the slide rails 8 by the pinions 8a, the tray 1 can be moved relative to the chassis 9 in the ejecting direction A by a distance "L" which is equal to the sum of the distance "La" and the distance "Lb".
As described above, the above tray guide mechanism 5 requires the movable rails 6 with the racks 6a, the fixed rails 7 with the racks 7a, and the slide rails 8 with the pinions 8a. The number of parts needed for the tray guide mechanism 5 is relatively large, and it takes a long time to assemble the disk apparatus with the tray guide mechanism 5.
Further, in order to assemble the disk apparatus with the tray guide mechanism 5, it is necessary that the slide rails 8 are movably attached at their ends to the movable rails 6 and movably attached at the other ends to the fixed rails 7. It is also necessary that the pinions 8a of the slide rails 8 are attached such that the pinions 8a are engageable with both the racks 6a of the movable rails 6 and the racks 7a of the fixed rails 7. It is further necessary that the movable rails 6 are secured to the tray 1 by the screws and the fixed rails 7 are secured to the chassis 9 by the screws.
Accordingly, when the above tray guide mechanism 5 is installed to the disk apparatus, the tray guide mechanism 5 is assembled with the movable rails 6, the fixed rails 7 and the slide rails 8, and the movable rails 6 are secured to the sides of the tray 1 by the screws and the fixed rails 7 are secured to the chassis 9 by the screws. The time to assembly the disk apparatus with the tray guide mechanism 5 is relatively long, and the assembly processes for the component parts of the tray guide mechanism 5 are complicated. Therefore, it is difficult for the above tray guide mechanism to increase the productivity and reduce the manufacturing cost.